Pipe forming machine



July 23, 1946. E. F. SEWELL PIPE FORMING MACHINE 2 Sheets-Sheet 1 Filed April 17, 1944 l NVENTOl Q. EF'ScwelL E. F. SEWELL 2,404,464

PIPE FORMING MACHINE I Filed April 17,.1944

July 23, 1946.

2 Sheets-Sheet 2 IQVENTOR I V E. F'Sewell M 74074.1:

ATTYS u I b l u I v mam v,

Patented July 23, 1946 UNITED STATES PATENT OFFICE PIPE FORMING MACHINE Earl F. Sewell, Yuba City, Calif.

Application April 17, 1944, Serial No. 531,456

13 Claims.

This invention relates to, and it is an object to provide, an improved machine for the manufacture of concrete pipe.

Another object of this invention is to provide a concrete pipe forming machine which is capable of producing concrete pipe rapidly, efiectively, in relatively long sections, and of relatively small diameter or bore, as well as in standard length sections and bores.

A further object of this invention is to provide a concrete pipe forming machine which will pack and form concrete having the proper watercement ratio to produce a mix having zero slump, and from which mix pipe of maximum strength can be obtained.

being open at opposite ends, and a power driven auger conveyor and packer initially extending centrally through said mold from end to end thereof and in clearance relation to its circumferential wall. The auger conveyor is operative to progressively feed the mix into the mold from end to end thereof to initially form the pipe and is then movable axially out of the mold; there being a packing and finishing head mounted in unitary connection with one end of the auger conveyor and functioning, when the auger conveyor is withdrawn from the mold, to further pack the mix and finish the inside of the pipe to correct diameter.

A further object of the invention is to produce a. simple and inexpensive device, and yet one which will be exceedingly effective for the purpose for which it is designed.

, These-objects I accomplish by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawings similar characters of reference indicate corresponding parts in the several views:

Figure l is a side elevation of the machine, partially .foreshortened.

Figure 2 is an enlarged transverse section on line 2--2 of Fig. 1.

Figure 3 is an end view, enlarged, of one form of the packing and finishing head. 7

Figure 4 is an enlarged fragmentary sectional elevation, foreshortened, illustrating the auger conveyor and packer being withdrawn from the mold after initial formation of the pipe section, and showing the packing and finishing head in operation.

Figure 5 is an enlarged elevation of a modified form of packing and finishing head, detached.

Figure 6 is an enlarged fragmentary elevation of a modified conveyor and packer, detached.

Referring now more particularly to the characters of reference on the drawings, the machine comprises a rigid base I disposed horizontally and supported above the floor. An axially elongated cylindricalmold or shell 2 is, disposed horizontally above the bed I and includes annular heads 3 re movably attached thereto by flanges 4 and securing bolts 5. The annular heads 3 extend radially out some distance beyond the mold 2 and are supported by transversely spaced V-groove rollers 6 disposed atv each end of and below the mold. Correspondingones of said rollers at opposite ends of the mold are mounted on a countershaft 1 which is driven from a motor 8 by means of an endless belt 9. It will be seen that the roll- -ers 6 form the support, as well as the drive, for

the mold 2, the latter being readily removable from the rollers to permit different molds to be successively used in the machine.

The mold 2 is formed of a pair of longitudinal half sections, as clearly shown in Fig. 2, and said sections, at adjacent edges, are formed with outwardly projecting matching flanges I0 detachably connected together by bolts l I.

The center openings l2 in the annular heads 3 are of substantially the same diameter as the inside diameter' of the pipe section to be formed in the mold 2, and the inner faces of the heads 3 are shaped, as shown at l3, to form the tongue and groove at opposite ends of the pipe section.

A hopper I4 is mounted on the base I beyond one end of the mold 2 and such hopper includes an open-ended body IS with one of said open ends in close register with the opening I2 in the'adjacent mold head 3.

Beyond the hopper M, in a direction lengthwise of the machine, the latter includes another bed 16 disposed horizontally but in a lower plane than the bed I such bed l6 including rails H on which a roller carriage i8 is movably supported. The carriage I8 is formed with an elevated platform is on which is mounted a pair'of longitudinally spaced but alined bearings 20. A. shaft 2| is jourof suitable power means, such as a fluid pressure actuated power cylinder23 connected between the carriage and one end of the bed l6. At' the end opposite the hopper body I5 the auger conveyor 22 includes a, projecting shaft 24 adapted to removably engage in an end bearing 25 mounted in fixed position in connection with the bed I. When the carriage I8 is in its advanced position, the shaft 24 is engaged in said bearing 25, whereby bearings and then support the auger conveyor 22 at opposite ends and maintain said auger. against undesirable lateral deflection when in operation. p I 7 i A cylindrical packing and finishinghead iii-is fixed on the shaft 24 between its outer end and the adjacent end of the auger conveyor 22; such,

packing and finishinghead being disposed outside of the mold 2 when the carriage I8 is advanced and the auger 22 extends through the mold from end to end thereof. The packing and finishing head 26 includes, at its lead end, a. plurality of substantially radially extending finishingblades or troweler shoes 21 adjustably secured to a mounting member 28 at oneend of said head 26. The finishing blades 21 are curved at their outer ends opposite the direction of rotation, and extend slightly outwardly I of the periphery of head 26. I

The unit, comprising the shaft 2 I, together with the auger 22, shaft 24, and packing and finishing head 26, is driven by means of an endless belt and pulley assembly 29 from an electric motor 30 mounted on and movable with the carriage I8.

. Operation In operation, the carriage is fully advanced to project the augerconveyor 22'through the mold 2 and until the shaft 24 seats in bearing 25. Thereafter the motors 8 and 39 are started, such motors driving the mold 2 and auger conveyor 22 in opposite directions; the speed of both the mold 2 and auger conveyor 22 being relatively slow. For example, the peripheral speed of the mold does not need to exceed 425 linear feet per minute. 1 With the'mold 2 and auger conveyor 22 rotat ing in opposite directions, the concrete mix is fed into the hopper l4 and is at once picked up from the hopper body l5 by the auger conveyor 22 and carried into the mold 2. The auger conveyor then functions to progressively distribute the mix in said mold from the end adjacent the hopper to the opposite end, and during the period of such distribution of the mix, it is also initially packed in the mold by the spiral vane 3| of the conveyor 22.

In order to facilitate this packing action the outer or working edge of vane 3| may be beveled, as at 32, with the bevel facing in the direction of rotation. This beveled edge of the vane 3| urges the mix into the pipe wall being formed, and consequently increases the density of such wall. The density of the pack can be controlled by the angle of the bevel 32. It should also be noted that due to the relatively slow speed of the mold 2,stratification of the aggregates in the mix does not occur, nor is there any leaching of the cement fromthe outside of said pipe wall.

The mix continues to be fed into the hopper I4 until the annular space between the auger conveyor and said mold is filled from end to end of the latter, as shown in Fig. 4.

When this occurs the feeding of the mix is stopped, and thereafter, with the mold and auger n conveyor 22 still being rotated in opposite directions, the carriage I8 is slowly retracted, which draws the auger conveyorfl22 slowly out of the mold 2. With such retraction'of the :auger conveyor 22 the p'ackingand finishing head 26 is drawn through the mold from end to end thereof,

producing a further packing, and an inside finish- 7 ;ing, ofthe pipe section 33, which hasbeen previ- I If any end slippage should occur during retraction of the conveyor 22 and movement of the packing and finishing head 26 through the pipe ously formed in the mold by said auger conveyor.

section 33, which end slippage would cause laterally inward shattering of the pipe wall, the conveyor 22 would'immediately pickup such shattered concrete and feed it; directly back-to the packing and finishing head. As a result, pipe sections are formed without imperfection.

When the auger conveyor 22 and packingand finishing head ZG are completely withdrawn from the mold 2, the latter is removed from the machine and transported tothe curing room; a Sp-r arate and empty mold then being replaced onithe machine for use in connection withthe formation of a further pipe section. i

In Fig. 5 there is illustrated a modified type of packing and finishing head which .comprises a cylindrical body 34 whose leading end portion is tapered inwardly, as at 35; this embodimento f the packing and finishing head employingno finishing shoes, as in the type shown in Figi 3. This form. of packing and finishing head maybe used when the consistency of the-mix does notemployed for the purpose of adjusting the blades 3! to compensate for wear.

From the foregoingdescription it will be readily seen that I have produced sucha device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device,.

still in practice such deviations from suchdetail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims. w

Having thus described my invention, whatI- claim as new and useful and desire to secure'by Letters Patent is: p

1; A concrete pipe forming machine comprising a horizontal base, a cylindrical horizontallydis' posed mold above the base, ineansonthe base removably supporting the mold for rota tion a hopper mounted on the base atone 'end of the mold, the hopper including a body openat oppo site ends and one end closely registering with the adjacent open end of themo'ld, a carriage mounted on the base beyond the hopper for move-'- ment parallel to the mold axis, an elongated. auger conveyor journaled at an end on the carriagef in.

ing through said body and from end to end of the mold when the carriage is advanced, and means to drive the conveyor and mold in opposite directions.

2. A concrete pipe forming machine comprising a horizontal base, a cylindrical horizontally disposed mold above the base, means on the base removably supporting the mold for rotation, a

hopper mounted on the baseat oneend of the.

mold, the hopper including a body open at opposite ends and one end closely registering with the adjacent open end of the mold, a carriage mounted on the base beyond the hopper for moveopening of a diameter only slightly larger than the conveyor.

3. A concrete pipe forming machine comprising a horizontal base, a cylindrical horizontally disposed mold above the base, means on the base removably supporting the mold for rotation, a hopper mounted on the base at one end of the mold, the hopper including a body open at opposite ends and one end closely registering with the adjacent open end of the mold, a carriage mounted on the base beyond the hopper for movement parallel to the mold axis, an elongated auger conveyor journaled at an end on the carriage in axial alinement with said open ended hopper body and the mold, said auger conveyor extending through said body and from end to end of the mold when the carriage is advanced, and means to drive the conveyor and mold in opposite directions; the conveyor including an axial shaft projecting freely from the end opposite the carriage, and a bearing mounted in connection with the base a distance beyond the end of the mold opposite the hopper, said shaft bein outside the drum and removably seating in said bearing when the carriage is advanced.

4. A concrete pipe forming machine as in claim 3 including a finishing and packing head mounted on said shaft, and said head being outside the mold when the carriage is advanced;

5. A concrete pipe forming machine comprising an open ended mold, a feed hopperdisposed adjacent one end of the mold and having its discharge opening in register with said end of the mold, an auger conveyor projecting through the feed hopper and through the length of the mold the longitudinal axis of the conveyor being in substantial alinement with the longitudinal axis of the mold, the edges of the convolutions of the auger conveyor being equally spaced from th side walls of the mold for the full circumference thereof, and the space between the peripheral edges of such convolutions and the walls of the hopper being freely open whereby material conveyed by the conveyor from the hopper will be progressively and uniformly packed along the length of the mold between the outer periphery of the conveyor convolutions and the side walls of the mold by the action of the conveyor, whereby to form the pipe and means to rotate the conveyor.

6. A device as in claim 5 in which the outer peripher of th convolutions of the auger is beveled to engage and compact and smooth the concrete as it is packed into the mold.

7. A device as in claim 5 including in combination therewith, means to withdraw the conveyor from the mold while continuing its rotation.

8. A device as in claim 5 including in combination therewith, means to withdraw the conveyor from the mold and means distinct from the conveyor but attached thereto to pack and finish the interior wall of the formed pipe as the conveyor is being withdrawn from the mold.

9. A device as in claim5 including in combination therewith, means to withdraw the conveyor from the mold, and a packing and finishing head on the outer end of the conveyor functioning upon withdrawal of the latter to pack and finish the interior wall of the formed pipe.

10. A concrete pipe forming machine comprising an open ended mold, an open ended feed hopper fixed adjacent the mold-with one open end in register with an open end of the mold, a carriage movable relative to the feed hopper and mold, and an auger conveyorjournal mounted on the carriage and adapted t be projected through the hopper and the length of the mold with movement of the carriage in one direction and to be retracted from the mold upon movement of the carriage in the opposit direction, and means to rotate the conveyor.

11. IA concrete pipe forming machine comprising an open ended mold, an open ended feed hopper disposed adjacent the mold with one open end of the hopper in register with one open end of the mold, a carriage movable toward and away from the feed hopper, a shaft journaled on the carriage and adapted to be moved longitudinally through the hopper and mold and to the full length of the mold, means to rotate the shaft, an anger disposed conveyor along the length of the shaft and which may be selectively projected through the hopper and mold or withdrawn therefrom.

12. A device as in claim 11 and in combination therewith a fixed journa1 adjacent the mold at the end opposite the end at which the hopper is disposed, the oute end of the shaft being adapted to move into and be supported by such bearing when the shaft has been advanced beyond the adjacent end of the mold.

13. A concrete pipe forming machine comprising an open ended mold, means to revolve the mold, an auger conveyor having its longitudinal feed material to the conveyor when it is within A the mold, the relative motions of the mold and conveyor then causing the material to be con-' veyed into the mold and packed into said space, a

packing head on the end of the conveyor and beyond the convolutions of the auger, the diameter I of said head being slightly greater than the diameter of the said convolutions whereby upon withdrawal of the auger from said mold such- 

